way to check an email without sending it??

Oliver Fromme olli at lurza.secnetix.de
Mon Oct 5 21:35:03 UTC 2009

Gary Kline <kline at thought.org> wrote:
 >         telnet couldn't connect for unknown reason but thabks for the tip.  I usually just

The mail server for a domain doesn't have to run on that
domain.  That's what MX records in DNS are good for.

For example, day, the address is cathy at example.org.
Then use this command to find the mail servers for that

$ host -t mx example.org

Every mail server has a priority number.  The lowest
number indicates the highest priority, i.e. the server
that should normally be tried first.  You should be
able to telnet to that server on the SMTP port.

If the MX list is empty, then either there is no mail
mail server for this domain at all, or the domain is
it's own mail server, i.e. you can telnet directly to
example.org on the SMTP port (provided that it has at
least an A record with a normal IP address).

By the way, in the good old days (i.e. before spam)
you could verify mail addresses with the SMTP VRFY
command.  But unfortunately, the days of spam have
changed many things.  :-(  Most mail servers don't
support VRFY anymore in order to protect against
the spammers' address harvesters.

Whatever you do to verify the address, it will not
be completely without a trace.  As soon as you connect
to the SMTP port, it might cause an entry in that
server's logfile, even before entering any SMTP command.

Best regards

Oliver Fromme, secnetix GmbH & Co. KG, Marktplatz 29, 85567 Grafing b. M.
Handelsregister: Registergericht Muenchen, HRA 74606,  Geschäftsfuehrung:
secnetix Verwaltungsgesellsch. mbH, Handelsregister: Registergericht Mün-
chen, HRB 125758,  Geschäftsführer: Maik Bachmann, Olaf Erb, Ralf Gebhart

FreeBSD-Dienstleistungen, -Produkte und mehr:  http://www.secnetix.de/bsd

"Whatever happened to the days when hacking started
at the cerebral cortex, and not at the keyboard?"
  --  Sid on userfriendly.org by Illiad, 2007-06-20

More information about the freebsd-questions mailing list